This invention relates to a natural coolant refrigerating plant.
More specifically, this invention relates to a natural coolant refrigerating plant used on machines for pasteurizing and/or producing confectionery products, such as ice creams, sorbets, custards, Bavarian cream and the like.
As is known, refrigerating plants used in machines for pasteurizing confectionary products not only heat the product in order to eliminate any bacteriological loads present, but also perform a subsequent cooling so as to carry the product to a suitable temperature for dispensing.
In other words, the coolant circulating in the plant is used as a heat exchange fluid, both for heating and cooling the product.
However, these plants need to use different coolant quantities or loads, depending on whether they are performing a product heating or cooling cycle.
More in detail, during the heating cycle, the plant would need a greater coolant load compared with that required during the cooling cycle.
Further, prior art natural coolant plants usually use a motor-driven compressor with two compression stages and they use a first heat exchanger, the so-cooled intercooler, for cooling the coolant flowing out from the first compression stage, and a second heat exchanger, the so-called gas-cooler, for cooling the coolant flowing out from the second compression stage.
The prior art plants which are able to both heat and cool the product being processed as described have the drawback of not being able to adequately control the requested coolant load.
More specifically, since a greater coolant load is requested during heating, these plants are usually designed according to this quantity of coolant.
However, during the cooling cycle, part of the coolant is not used, since it is not necessary.
As this part of the coolant is not used, there is a consequent lowering of the overall efficiency of the plant.
Further, even during the heating cycle the plant would still not be able to use this quantity of coolant, which would often remain entrapped inside the intercooler.
Thus, there would be a reduction in the overall efficiency of the plant even during the heating cycle.